Why was hydrogen the first atom in the universe?

524 viewsOtherPhysics

To my understanding, at the very beginning there was the big bang when nothing (or everything?) existed in singularity, and then at some early point hydrogen came to existence. I understand how stars churn with gravity and heat and whatnot those bigger atoms such as iron at later stages of the universe. But how and why did hydrogen happen as the first atom, and why didn’t we have, say, uranium straight from the beginning?

In: Physics

9 Answers

Anonymous 0 Comments

We also had also lots of helium at the beginning, and probably a tiny bit of lithium. The initial ultra-hot soup of energy and particles after the big bang cooled (read: still extremely hot, just a bit less so) to the point where stuff flying around was mostly protons, neutrons, and electrons. But the heat was still immense and baked them together into slightly larger atoms sometimes, creating deuterium and helium mostly.

But larger stuff was not able to survive in those conditions. A very strong burst of light can literally rip an atomic nucleus apart, and this is easier for heavy stuff. So that tiny bit that maybe was created, if at all, was getting destroyed right away by a still _very_ hot and _bright_ early universe.

You are viewing 1 out of 9 answers, click here to view all answers.